Fuel feeder

ABSTRACT

The system has a fuel pump disposed in a fuel tank for raising a pressure of a fuel sucked through an intake filter and discharging the fuel, a pressure regulator for regulating the pressure of the fuel discharged from a discharge port, a fuel filter for filtering the fuel discharged from the discharge port, and a pump holding case for hermetically covering the fuel pump and accommodating and holding the fuel pump. A cushion rubber, having a passage for communicating an intake port and the intake filter is interposed between a bottom wall of the pump holding case and the fuel pump.

TECHNICAL FIELD

The present invention relates to a fuel supply apparatus or supplying afuel to an engine using a fuel pump disposed in a fuel tank.

BACKGROUND ART

Hitherto, a apparatus described in the International PublicationNo.WO96/23966 has been known as a fuel supply apparatus for supplying afuel to an engine. This apparatus is a unified construction in which afuel pump is accommodated in a pump case through a rubber member, anintake filter is connected to an intake pipe of the fuel pump, a fuelfilter for filtering a fuel discharged from the fuel pump isaccommodated in a filter case, and the pump case and the filter case areengaged by snap-fitting.

However, in the -construction described in the International PublicationNo.WO96/23966, the intake pipe side of the fuel pump is exposed tooutside from the pump case, and consequently, any noise generated on theintake side of the fuel pump is directly transmitted to the inside ofthe fuel tank. Such a noise is heard from outside of the fuel tank. Theintake pipe of the fuel pump is approximately L-shaped, which is easy togenerate a noise when the fuel is sucked. Moreover, the fuel pump andthe pump case required to be positioned with respect to the rubbermember and the intake pipe respectively, and therefore this apparatus isinferior in assembling efficiency.

DISCLOSURE OF INVENTION

The present invention was made to solve the above-discussed problems andhas an object of obtaining an improved fuel supply apparatus of simplestructure capable of reducing a noise generated when the fuel pump sucksa fuel.

A fuel supply apparatus according to the invention is a fuel supplyapparatus for supplying a fuel to an engine comprising:

a fuel tank; a cylindrical fuel pump disposed in the mentioned fuel tankfor raising a pressure of the fuel sucked from an intake port thereofand discharging the fuel from a discharge port thereof; an intake filterfor filtering the fuel in the mentioned fuel tank and supplying the fuelto the intake port of the fuel pump; a pressure regulator for regulatinga pressure of the fuel discharged from the discharge port of thementioned fuel pump; and a holding case hermetically covering at leastthe intake port side of the fuel pump and accommodating, and holding thefuel pump. As a result of such construction, it is possible to reduceany noise generated when the fuel pump sucks the fuel and simplify thestructure.

The holding case is provided with a first connecting portion to beconnected to a fuel filter and a second connecting portion to beconnected to the intake port of the fuel pump. As a result, it ispossible to further reduce the noise generated when the fuel pump sucksthe fuel. The intake port of the second connection portion of theholding case are connected through a bypass formed by a rubber memberdisposed in the holding case. As a result, it is not necessary to usespecial connecting pipe for connecting them, and number of parts can bereduced as to compare with prior apparatus.

The rubber member is interposed between the fuel pump and the holdingcase, and serves as a cushion for the mentioned fuel pump. As a result,the system is small-sized and the system is assembled easily.

The bypass is formed with a groove provided on the rubber member and aninner peripheral wall of the holding case, and the mentioned groove isformed to communicate to the second connecting portion of the holdingcase and to the intake port of the fuel pump. As a result, the system isassembled easily.

The rubber member is interposed between an outer circumference of thefuel pump and an inner circumference of the holding case and is providedwith a partition for partitioning the bypass. As a result, only the fuelthat has passed through the intake filter is supplied to the bypass, andthe fuel is supplied stably.

The holding case hermetically accommodates the pressure regulator and isprovided with a fuel holding portion for holding the fuel dischargedfrom the pressure regulator and a flowing out portion for flowing outthe fuel to the fuel tank when the fuel in the mentioned fuel holdingportion exceeds a predetermined amount. As a result, it is possible toreduce the noise generated when the fuel passes through the pressureregulator.

The flowing out portion is formed into plural holes. As a result, it ispossible to reduce the noise generated when the fuel is flowed out fromthese holes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a schematic view of a fuel supply apparatus according toEmbodiment 1 of the invention.

FIG. 2 is a partially enlarged sectional view showing a fuel pump unitof the fuel supply apparatus in FIG. 1.

FIG. 3 is a top view of the fuel pump unit portion in FIG. 2.

FIG. 4 is a sectional view taken along the line IV—IV in FIG. 2.

FIG. 5 is a sectional view taken along the line V—V in FIG. 2.

FIG. 6 is an enlarged sectional view showing the fuel pump intake sideFIG. 2.

FIG. 7 is a sectional view taken along the line VII—VII in FIG. 6.

FIG. 8 is a sectional view taken along the line VIII—VIII in FIG. 6.

FIG. 9 is a schematic view for explaining the assembling of an intakefilter according to Embodiment 1.

FIG. 10 is a partially enlarged sectional view showing a cushion rubberportion of a fuel supply system according to Embodiment 2 of theinvention.

FIG 11 is a sectional view taken along the line XI—XI in FIG. 10.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the invention are hereinafter described in detail.

Embodiment 1

FIG. 1 is a schematic view of a fuel supply apparatus according toEmbodiment 1 of the invention. In FIG. 1, reference numeral 100 is afuel tank made of a metal for accommodating a fuel 102, and the fueltank 100 is provided with an opening 108 in which a fuel pump unit 200is inserted. Numeral 200 is the fuel pump unit including a fuel pump(F/P) 210 for raising a pressure of the fuel 102 and discharging it, apressure regulator (P/R) 220 for keeping the discharging pressure of thefuel pump 210 at a predetermined value, and a fuel filter (F/F) 230 forfiltering the fuel discharged from the fuel pump 210. Numeral 270 is aflange made of a metal for sealing the opening 108 fluid-tight afterinstallation of the fuel pump unit 200, and numeral 272 is a deliverypipe for delivering the fuel supplied from the fuel pump unit 200 to anengine not shown.

FIG. 2 is a partially enlarged sectional view showing the fuel pump unitof the fuel supply apparatus in FIG. 1. FIG. 3 is a top view of the fuelpump unit portion in FIG. 2. FIG. 4 is a sectional view taken along theline IV—IV in FIG. 2. FIG. 5 is a sectional view taken along the lineV—V in FIG. 2. In FIG. 5, sectional illustration of the fuel pump, isomitted.

In FIG. 2, numeral 202 is an intake filter for sucking and filtering thefuel 102 from the fuel tank 100 when the fuel pump 210 is driven. Theintake filter 202 is composed of a mesh portion 204 made of a nylonmaterial or the like and a bush portion 206 for pressing and insertingthe mesh portion 204 into a connecting portion (a first connectingportion) 250 a of a pump holding case 250 and connecting them.

Numeral 210 is, for example, a Westco type fuel pump disclosed inJapanese Patent Publication (examined) No. 63756/1988. When a drivingpower is supplied through a connector 274 (see FIG. 3), the fuel pump210 raises a pressure of the fuel sucked from an intake port 212 anddischarges the fuel from a discharge port 214. In the drawing, powerline and control line for connecting the connector 274 and the fuel pump210 are not shown. The fuel pump 210 is fixed by an inner bottom wall250 c (the lower side in FIG. 2) of the pump holding case 250 through acushion rubber (rubber member) 216 mounted on a pump cover 213 formedby, for example, aluminum die-casting on the intake port 212 side (lowerside in FIG. 2). The fuel pump 210 is also fixed to a retaining portion262 a through a rubber bush 218 having a through hole for passing thefuel passes on the discharge port 214 side (upper side in FIG. 2).

The cushion rubber 216 positions and fixes the fuel pump 210, andfurther serves as a passage for guiding the fuel sucked from the intakefilter 202 through connecting portions 250 a and 250 b to the intakeport 212. The cushion rubber 216 is composed of an elastic body such asbutyl nitrile rubber or fluorine rubber.

Now, construction of the cushion rubber 216 is hereinafter describedwith reference to the drawings. FIG. 6 is an enlarged sectional viewshowing the fuel pump intake side in FIG. 2. FIG. 7 is a sectional viewtaken along the line VII—VII in FIG. 6, and FIG. 8 is a sectional viewtaken along the line VIII—VIII in FIG. 6.

Numeral 216 a is a passage (bypass) comprised of an intake portion 216 a1 , a case-side communicating groove 216 a 2, a return portion 216 a 3,and a pump-side communicating groove 216 a 4. The intake portion 216 a 1is formed being partitioned by a tapered portion 216 e, the inner bottomwall 250 c and a side wall 216 f (see FIG. 8) of the cushion rubber 216,and communicates to the connecting portion (the second connectingportion) 250 b that is an opening on an inner side of the pump holdingcase 250. As a result of forming the tapered portion 216 e, the fuel canbe smoothly guided in the direction of an arrow B1. The connectingportion 250 b is formed long in the height direction (the up-and-downdirection in FIG. 6) with respect to a tapered face of the taperedportion 216 e, which results in effective reduction in pressure loss offlow.

The case-side communicating groove 216 a 2 is formed being partitionedby a rectangular parallelepiped-shaped groove with bottom portions 216 d1, 216 d 2, and 216 d 3 (see FIG. 8) of the cushion rubber 216, theinner bottom wall 250 c, and a plate-shaped portion 216 d 4. The fuelpasses in the direction of an arrow B2, reaches the return portion 216 a3 communicating to an end of the case-side communicating groove 216 a 2,thus the fuel is conveyed in the direction of an arrow B3. The returnportion 216 a 3 is an opening provided on the plate-shaped portion 216 d4.

The pump-side communicating groove 216 a 4 is formed into a shortcylindrical configuration with the plate-shaped portion 216 d 4 and thepump cover 213. As indicated by an arrow B4, the fuel is sucked into thefuel pump 210 through the intake port 212 provided at an end of thepump-side communicating groove 216 a 4.

Numeral 215 is a vent hole provided on the pump cover 213, and numeral216 c is a vent hole provided on the plate-like portion 216d4 of thecushion rubber 216 and communicating to the vent hole 215. Numeral 255is a vent hole provided on the pump holding case 250 and communicatingto the vent hole 216 c. Gas produced during the process of raising thepressure in the fuel pump 210 passes through the vent holes 215, 216 c,and 255 and is discharged to outside of the fuel pump unit 200 asindicated by an arrow J.

Returning to FIG. 2, numeral 220 is the pressure regulator for keepingthe pressure of the fuel discharged from the fuel pump 210 at apredetermined value. The pressure regulator 220 is press-fitted in aretaining portion 264 of a filter holding case 260 through an O-ring222, and the other side thereof is fixed by ribs 250 d 1, 250 d 2, and250 d 3 (see FIGS. 2 and 5) of the pump holding case 250.

Numeral 230 is a hollow cylindrical fuel filter for filtering the fueldischarged from the fuel pump 210, and comprises a filtration element232 composed of a filter paper or the like and a holding member 234 forkeeping the filtration element 232 held in the filter holding case 260.After inserting the filter 230 in the filter holding case 260 andholding it by the holding member 234, a cover member 262 is joined tothe filter holding case 260, or they are integrally welded together.

Numeral 240 is a check valve that is disposed in a passage on an opening238 (see FIG. 4) side of the fuel filter 230 and keeps the pressure inthe delivery pipe 272 when stopping the engine. The check valve 240 ispositioned with respect to a holding portion 262 b of the filter holdingcase 260 (the cover member 262) and the flange 270 through a rubber bush242 provided with a through hole.

Numeral 250 is the pump holding case for hermetically covering theintake port side of the fuel pump 210 to accommodate and hold the fuelpump 210. Molding a thermoplastic resin such as polyacetal, for example,forms the pump holding case 250. The pump holding case 250 is fixed tothe filter holding case 260 by engaging an engaging hole 254 of the pumpholding case 250 with an engaging claw 266 of the filter holding case bysnap fitting. A center gauge 284 (see FIG. 5) for detecting a level, ofthe fueling the fuel tank 100 is attached to the outer periphery of thepump holding case 250. The filter holding case 260 is provided with acenter gauge harness 286 (see FIG. 4) for supporting the center gauge284. The connecting portions 250 a and 250 b are integrally formed withthe pump holding case 250 by a resin.

Numeral 260 is the filter holding case fixed to the flange 270 byengaging an engaging claw with an engaging hole not shown by snapfitting.

Numeral 270 is a flange fixed fluid-tight to the fuel tank 100 by a sealpacking (not shown) attached to a collar portion 276 of the flange 270.The flange 270 is provided with a breather pipe 280 (see FIG. 3) and acut-off valve 282.

Numeral 278 is a fuel-flowing out hole (outlet) provided on the flange270. When more than a predetermined amount of fuel delivered from thepressure regulator 220 flows into a fuel holding portion 290, the fuelis flowed out from the fuel pump, unit 200 to the fuel tank 100 throughthis fuel-flowing out hole 278. It is preferable to form pluralfuel-flowing out holes 278 in order to reduce the noise generated at thetime of flowing out the fuel to the fuel tank 100.

The fuel holding portion 290 is comprised of a space 290 a formed amongthe inner wall of the pump holding case 250, the fuel pump 210, and thepressure regulator 220, a crescent-shaped space 290 b (see FIG. 4)formed between the fuel pump 210 and the fuel filter 230 in the filterholding case 260, and a space 290 c formed between the inner wall of theflange 270 and internal components thereof (more specifically, the covermember 262, the breather pipe 280 and the cut-off valve 282).

In this embodiment, the holding case as set forth in claims is comprisedof three members, i.e., the pump holding case 250, the filter holdingcase 260, and the flange 270. It is also preferable that instead ofthese three members, one member, two members, or three or more membersform the holding case, thus number of the members is not limited tothree.

Assembling

Now, assembling the fuel supply system is described.

First, the fuel filter 230 is held by the filter holding case 260, thecover member 262 is joined to the filter holding case 260, or the covermember 262 and the filter holding case 260 are integrally welded, andthereafter, the rubber bush 218 is mounted on the discharge port of thefuel pump 210, and this fuel pump 210 is press-fitted in the covermember 262.

Subsequently, under the state of fitting the 0-ring 222 on the pressureregulator 220, the pressure regulator 220 is press-fitted in the filterholding case 260. The cushion rubber 216 is mounted on the side of theintake port 212 of the fuel pump 210. In this process, referring to FIG.6, an outer periphery side of an annular protrusion 213 a of the pumpcover 213 is fitted and fixed to a fitting portion 216 g of the cushionrubber 216, and a partition 216 b is fitted and fixed to an outerperiphery of the fuel pump 210. Then, the pump holding case 250 isattached to the filter holding case 260 by snap-fitting engagement. Atthis time, the partition 216 b of the cushion rubber 250 is interposedfluid-tight between the fuel pump 210 and the inner wall of the pumpholding case 250. Furthermore, referring to FIG. 6, an annularprotrusion portion 216 b 1 formed on the partition 216 b fits in anannular groove 253 formed on the pump holding case 250, and an annularprotrusion portion 216 b 2 formed on the partition 216 b fits in anannular groove 213 b formed on the pump cover 213, and consequently,they are fixed fluid-tight and positioned with accuracy.

Now referring to FIG. 9, the intake filter 202 is described. FIG. 9 is aschematic view to explain assembling of the intake filter. The pumpholding case 250 is integrally provided with the connecting portion 250a having a through hole 250 a 1 by resin molding. The bush portion 206is comprised of an insert portion 206 a to be press-fitted in thethrough hole 250 a 1 of the connecting portion 250 a, an annular portion206 b having an external form larger than the insert portion 206 a toinhibit further insertion into the through hole 250 a 1, and a throughhole 206 c provided through the center of the insert portion 206 a andthe annular portion 206 b. To mount the intake filter 202 on the pumpholding case 250, the press-fitted portion 206 a of the bush portion206, passing through the mounting hole 204 a of the filter portion 204,is inserted in the through hole 250 a 1 of the connecting portion 250 aby press-fitting. In this process, it is preferable to interpose asealing member not shown in the drawings between the press-fittedportion 206 a and the through hole 250 a 1 in order to seal them morehermetically.

Subsequently, the check valve 240 is disposed in the filter holding case260 (the cover member 262), and after mounting the filter holding case260 on the flange 270 under the state of fitting the rubber bush 242 onthe check valve 240, this fuel pump unit 200 is inserted from theopening 108 of the fuel tank 100. Then the collar portion 276 is screwedin and fixed to the fuel tank 100 through a blanket and a seal packingnot shown.

Fuel Supply Operation

Now, operation of supplying the fuel is described. In FIG. 2, arrows Ato H indicate flow of the fuel.

When; a driving power is supplied from the connector 274 and a commandto supply the fuel to the engine not shown is received from a controlsystem not shown, the fuel pump 210 starts its operation.

By the operation of the fuel pump 210, the fuel 102 in the fuel tank 100passes through the intake filter 202, passes through the connectingportion 250 a and the connecting portion 250 b of the pump holding case250 as indicated by the arrow A, passes through the passage 216 a in thecushion rubber 216 as indicated by the arrow B, and is sucked from theintake port 212 of the fuel pump 210.

An impeller not shown rotates to raise the pressure of the fuel suckedinto the fuel pump 210, and after the fuel is discharged from thedischarge port 214, the fuel passes through a passage 263 provided inthe filter holding case 260 as indicated by the arrow C.

If the pressure of the fuel that has passed through the passage 263 andis almost reaching the fuel filter 230 is higher than a predeterminedvalue, the fuel is kept at the predetermined pressure by being branchedinto the pressure regulator 220 as indicated by the arrow D. The rest ofthe fuel passes through the filtration element 232 from an opening 236of the fuel filter 230 as indicated by the arrow E and arrow F and isdischarged from the opening 237. In addition, the pressure regulator 220is disposed on the upstream side (the fuel tank 100 side) of the fuelfilter 230 in this example. It is also preferable that the pressureregulator 220 is disposed on the downstream side of the fuel filter 230.

The fuel discharged from the opening 237 passes through the check valve240, passes through the delivery pipe 272 as indicated by the arrow Gand arrow H, and is supplied to the engine through an injector nowshown.

As described above, the intake port 212 side of the fuel pump 210 ishermetically covered with the pump holding case 250, and therefore anynoise generated near the intake port 212 when the fuel is sucked is shutoff and is hardly conveyed directly to the outside of the fuel pump unit200, i.e., to the inside of the fuel tank 100.

The connecting portion 250 a protrudes from the pump holding case 250,and therefore any noise generated near the intake port 212 when the fuelis sucked is shut off and is hardly conveyed directly to the inside ofthe fuel tank 100.

The connecting portion 250 a is integrally formed with the pump holdingcase 250, and therefore it is possible to dispose the intake filter 202easily and increase rigidity of the connecting portion 250 a as comparedwith the case of directly connecting the fuel pump 210 to the intakefilter 202 by a tubular member.

The connecting portions 250 a and 250 b are provided on the pump holdingcase 250, and the cushion rubber 216 is provided with the passage 216 afor connecting the connecting portion 250 b to the intake port 212. As aresult, number of parts is reduced and the apparatus is easily assembledas compared with the conventional construction in which the intakefilter and the intake port are connected by a connecting pipe and thefuel pump is supported by the pump holder through the rubber member.

The passage 216 a of the cushion rubber 216 is U-shaped, and thereforeany noise generated near the intake port 212 when the fuel is sucked ishardly conveyed to the inside of the fuel tank 100.

The passage 216 a of the cushion rubber 216 is U-shaped in the axialdirection of the fuel pump 210 (the direction in which “U” is turned 90°counterclockwise in the sectional view shown in FIG. 6). As a result, itis possible to locate the intake port 212 of the fuel pump 210 close tothe connecting portions 250 a and 250 b, thereby the noise beingeffectively reduced. In addition, the intake port 212 of the fuel pump210 is provided in the pump cover 213, i.e., any intake pipe is notconnected. It is therefore possible to shorten the fuel pump 210 in theaxial direction and to small size the fuel pump unit 200.

Only a space for interposing the cushion rubber 216 is required betweenthe intake port 212 side of the fuel pump 210 and the inner bottom wall250 c of the pump holding case 250. It is therefore possible to shortenthe pump holding case 250 in the longitudinal direction (in the axialdirection of the fuel pump 210) and to small size the fuel pump unit200.

The fuel pump 210 is disposed in the pump holding case 250 through theelastic cushion rubber 216, and therefore any play to a certain extentis permissible and the system is easily assembled.

The partition 216 b of the cushion rubber 216 separates the fuel thatpassed through the intake filter 202 from the fuel that passed throughthe pressure regulator 220, and therefore the entire constructionbecomes simple and the system is easily assembled.

The pressure regulator 220 is hermetically covered with the pump holdingcase 250, and therefore it is possible to shut off any noise generatedwhen the fuel passes through the pressure regulator 220.

The fuel discharged from the pressure regulator 220 is not directlydischarged into the fuel tank 100 but is temporarily held in the holdingcase comprised of the pump holding case 250, the filter holding case 260and the flange 270. Then a portion of the fuel exceeding a predeterminedamount is discharged from the fuel-discharging hole 278. As a result,the discharged fuel flows along the holding case into the fuel tank 100,whereby it is possible to reduce generation of noise.

In addition, for the purpose of reducing only the noise generated fromthe pressure regulator 220, it is not always necessary to hermeticallycover the intake side of the fuel pump 210.

Embodiment 2

FIG. 10 is an enlarged sectional view showing a cushion rubber portionof a fuel supply apparatus according to Embodiment 2 of the invention.FIG. 11 is a sectional view taken along the line XI—XI in FIG. 10. Inthe drawings, numeral 316 is a cushion rubber having a spiral passage316 a and a partition 316 b interposed fluid-tight between the fuel pump210 and the inner wall of the pump holding case 250. The passage 316 ais comprised of an opening portion 316 a 1 communicating to theconnecting portion 250 b of the pump holding case 250, a passage portion316 a 2 forming a spiral passage with the inner wall of the pump holdingcase 250, and a joining portion 316 c provided at an end of the passageportion 316 a 2 and in which an intake pipe 212B of the fuel pump 210 ispress-fitted. Height (dimension in vertical direction in FIG. 10) of theopening portion 316 a 1 is formed to be smaller than a communicationhole (equivalent to numeral 206 in FIG. 6) of the connecting portion 250b. Length of the opening portion 316 a 1 is formed to be larger than thecommunicating hole in the circumferential direction (length in theclockwise direction in FIG. 11). Description of a vent for dischargingany gas generated at the time of raising the pressure in the fuel pump210 is omitted in Embodiment 2. The rest of the construction is the sameas that in the foregoing Embodiment 1, and the description is omitted.

As described above, the passage 316 a is formed to be spiral. Thereforeany noise generated near the intake pipe 212B when the fuel is suckedare not directly conveyed to the inside of the fuel pump 100.Furthermore the cushion rubber 316 can be formed to be small in height(length in the vertical direction in FIG. 11) and it is possible tosmall size the fuel pump unit 200.

The opening portion 316 a 1 is lower than the communicating hole, and itis therefore possible to arrange the fuel pump 210 close to a bottomwall of the pump holding case 250 and small size the fuel pump unit 200.

The opening portion 316 a 1 is longer than the communicating hole in thecircumferential direction, and it is therefore possible to reducepressure loss of the flow.

The intake pipe 212B is press-fitted in the joining portion 316 c of thecushion rubber 316, and therefore the intake pipe 212B is easilypositioned. It is also preferable that the intake pipe 212B is providedin the form of a recession on the pump cover 213 in the same manner asin the foregoing Embodiment 1. In this case, it is possible to smallsize the fuel pump unit 200 in the direction of height (axial directionof the fuel pump 210).

Industrial Applicability

The invention described above is applicable to devices having enginessuch as motor bicycles, snowmobiles, etc. other than vehicles.

What is claimed is:
 1. A fuel supply apparatus for supplying a fuel toan engine comprising: a fuel tank; a cylindrical fuel pump disposed insaid fuel tank for raising a pressure of the fuel sucked from an intakeport thereof and discharging the fuel from a discharge port thereof; anintake filter having a filter connecting portion for filtering the fuelin said fuel tank and supplying the fuel to the intake port of said fuelpump; a pressure regulator for regulating a pressure of the fueldischarged from the discharge port of said fuel pump; a holding casecovering at least the intake port side of said fuel pump andaccommodating and holding said fuel pump; and a rubber member disposedin said holding case and interposed between the intake port side of saidfuel pump and an inner surface of said holding case, wherein saidholding case is integrally formed with a case connecting portion inwhich the filter connecting portion of said intake filter ishermetically connected and said holding case substantially andhermetically covers the intake port side of said fuel pump with theexception of the case connecting portion, said intake filter covers thecase connecting portion of said holding case, and said rubber memberforms at least a part of passage communicating the intake port of saidfuel pump to the case connecting portion of said holding case.
 2. Thefuel supply apparatus according to claim 1, wherein the holding caseincludes a first connecting portion to be connected to a fuel filter,and a second connecting portion to be connected to the intake port ofthe fuel pump.
 3. The fuel supply apparatus according to claim 2,wherein the intake port of the fuel pump and the second connectingportion of the holding case are connected through the bypass formed bythe rubber member disposed in said holding case.
 4. The fuel supplyapparatus according to claim 3, wherein the rubber member serves as acushion for said fuel pump.
 5. The fuel supply apparatus according toclaim 3, wherein the rubber member is interposed between an outercircumference of the fuel pump and an inner circumference of the holdingcase and is provided with a partition for partitioning the bypass. 6.The fuel supply apparatus according to claim 1, wherein the holding casehermetically accommodates the pressure regulator and is provided with afuel holding portion for holding the fuel discharged from the pressureregulator and a flowing out portion for flowing out the fuel to the fueltank when the fuel in said fuel holding portion exceeds a predeterminedamount.
 7. The fuel supply apparatus according to claim 6, wherein theflowing out portion is formed into plural holes.
 8. A fuel supplyapparatus for supplying a fuel to an engine comprising: a fuel tank; acylindrical fuel pump disposed in said fuel tank for raising a pressureof the fuel sucked from an intake port thereof and discharging the fuelfrom a discharge port thereof; an intake filter having a filterconnecting portion for filtering the fuel in said fuel tank andsupplying the fuel to the intake port of said fuel pump; a holding casecovering at least the intake port side of said fuel pump andaccommodating and holding said fuel pomp; and a rubber member disposedin said holding case and interposed between the intake port side of saidfuel pump and the inner surface of said holding case, wherein saidholding case is integrally provided with a case connecting portion inwhich the filter connecting portion of said intake filter ishermetically connected and said holding case substantially andhermetically covers the intake port side of said fuel pump withexception of the case connecting portion, said intake filter covers thecase connecting portion, and said rubber member forms at least a part ofpassage communicating the intake port of said fuel pump to the caseconnecting portion of said holding case.